Means for balanced dispatching of odd and even numbers of elevator cars



Dec. 23, 1952 AZY 2,623,110

W. A. NIK MEANS FOR BALANCED DISPATCHING OF ODD AND EVEN NUMBERS OF ELEVATOR CARS Filed Oct. 19, 1951 7'0 44-6 ,5. START sw/raw n FOR CAR F T0 M-G E START SWITCH FOR OAR H r0 u-a snmr sw/rcn FQR can I TO MG STARTSWIEH Fm OAR I LOWER TERMINAL l3 UPPER TERMINAL SCHEDULING RELAY SCHEDULING RELAY ZSmaentor WAL 75/? A. N/KAZY (Ittornegi Patented Dec. 23, 1952 MEANS FOR BALANCED DISPATCHING F IODD AND EVEN NUMBERS OF ELEVATOR CARS Walter A. Nikazy, Toledo, Ohio, assignor to Haughton Elevator Company, Toledo, Ohio, a

corporation of Ohio Application October 19, 1951, Serial No. 252,102

11 Claims. 1

This invention relates to elevator control systems and particularly to means for maintaining a balanced relationship between the cars of a bank of elevators serving down traffic and the cars serving up traffic.

When traflic is approximately equal in both directions, regular elevator service to all floors is best provided by dispatching the cars at regular intervals from each of the terminals of the bank of elevators. When an odd number of cars, such as three or five, is in operation the balance between the cars devoted to up traffic and the cars devoted to down traflic is attained by dispatching cars alternately from the upper and lower terminals. When an even number of cars, such as two or four, is in operation the balance betweenthe cars devoted to up traffic and the cars devoted to down trafilc is attained by dispatching a car from the upper terminal simultaneously with each dispatch of a car from the lower terminal.

In a typical control system, such for example, as that illustrated and described in United States Patent No. 1,966,071, dated July 10, 1934, a mechanical or electric timing device is employed to space the dispatch signals at equal intervals and to keep the dispatch signals to the lower and upper terminals in step with each other. At the end of each interval the timing device closes two contacts, the first of which is in a circuit that sends dispatch signals to the lower terminal, the second of which can be switched into a circuit that sends dispatch signals to the upper terminal. At the midpoint of each interval the timing device closes a third contact which can be switched into a circuit that dispatches signals to the upper terminal. The switching mechanism is so arranged that manipulating the mechanism to switch in the third contact will switch out the second contact, and vice versa.

Apparatus such as that so far described serves its purpose if the human elevator starter always switches from alternate lower and upper terminal dispatching to simultaneous lower and upper terminal dispatching whenever the number of cars in operation is changed from odd to even, and always switches back to alternate dispatching whenever the numberof cars is changed "back to odd. However, if, as often happens, the starter forgets or neglects, when the number of cars is changed, to switch from alternate dispatching to r simultaneous dispatching or to switch back to alternate dispatching, the service becomes irregular.

It is an object of this invention to provide means for automatically causing dispatch signals to be given alternately to lower and upper termi 2 nals at regular intervals whenever an odd number of elevators of a bank is in operation, and for automatically causing dispatching signals to be given simultaneously to both terminals at regular intervals whenever an even number of elevators is in operation.

Other objects will be apparent from the following description illustrated by the accompanying drawing which is a diagram of apparatus embodying the instant invention, the apparatus being diagrammed in condition to send dispatch signals alternately to the lower and upper terminals of a bank of five elevators when all five of the elevators are inoperation.

Any suitable type of timing device may be employed with the apparatus of the'instantinvention. For simplicity of illustration the drawing shows a motor I with reduction gearing 2 which turns a shaft 3 upon which are mounted contact closing cams 4, 5 and 6. The cam 4 closes a contact I at each revolution of the shaft 3 thus completing a circuit through a lower terminal scheduling relay 8, which may be of any desired form and which, therefore, is shown by block diagramming. When the circuit through the relay 8 is completed by the closing of the contact I a dispatch signal is sent in the well-known manner to the lower terminal of the bank of elevators. Thus dispatch signals are flashed or sounded at the lower terminal at regular intervals, one for each revolution of the shaft 3.

The cam 5 closes a contact 9 simultaneously with the closing of the contact 1 at each revolution of the shaft 3. Closing of the contact 9 does not, however, complete a circuit as long as another contact 10 of the circuit remains open.

The earn 6 closes a contact H at each revolution of the shaft, the contact I I being closed half a revolution after the closing of the contact 1.

The contacts 7 and I I thus are closed alternately.

In series with the contact H is a contact [2 which when closed permits completion of a circuit through an upper terminal scheduling relay l3 whenever the contact H is closed. The relay I3 is similar to the relay 8 and likewise is shown by block diagramming. When the circuit through the relay I3 is completed by the closing of the contact I l, a dispatch signal is sent in the wellknown manner to the upper terminal of the bank of elevators. Thus, when the contact I2 is closed and the contact H3 is opened, dispatch signals are sent alternately to the lower and upper terminals, one signal to each terminal during each revolution of the shaft 3.

The contacts i5 and 52 are connected to a relay M, which when activated opens the contact i6 and closes the contact H2. The relay M is energized by a circuit which is completed whenever the number of cars in operation is odd, and is broken whenever the number of cars in operation is even.

Wired into a circuit with the motor-generator start switch that must be closed to put car I of a bank of elevators into operation is the coil of a relay 15. (In the drawing motor-generator start switch leads are labeled To M. G. Start Switch I, II, III, etc.) When the coil of the relay is energized, a contact it is opened and a contact H is closed.

Wired into a circuit with the motor-generator start switch that is closed to put car II into operation is a relay I8 which is connected to contacts I9, 2B, 21 and 22. When the coil of the relay i8 is energized certain contacts 2!} and 2| are closed and other contacts is and 22 are opened.

Wired into a circuit with the motor-generator start switch that is closed to put car III into operation is a relay 23 which is connected to contacts 2 25, 2e and 21. When thecoil of therelay 23 is energized certain contacts 25 and 25 are closed and other contacts 24 and 2'1 are opened.

Wired into a circuit with the motor-generator start switch that is closed to put car IV into operation is a relay 28 which is connected to contacts 29, 30, 3| and 32. When the coil of the relay 2'3 is energized certain contacts 33 and 3! are closed and oth r contacts 29 and 32! are opened.

Wired into the circuit with the motor-generator start switch that is closed to put car V into operation is a coil of a relay 3%. When the coil of the relay 33 is energized, a contact Ell is opened and a contact 35 is closed.

When all the motor-generator start switches are closed and cars I, II, III, IV and V are in operation, current may pass through contacts ll, 2|, 2e, 3| and 35, as well as through the coil of the relay it, which when energized closes the contact [2 and permits current to flow through the contact I l whenever it is closed by the cam 6. Thus with the apparatus in the condition in which it is diagrammed, dispatch signals are sent alternately to the lower and upper terminals as the contacts I and I! are closed alternately by the cams 4 and 6.

If the motor-generator start switch for car I is opened the coil of the relay 8% is deenergized, thus closing the contact it and opening the corn tact ll. With the contact ll open and the contact i6 closed, current cannot flow through the relay l4 because the circuit which includes the contact l6 and the contacts 29, 25 and 36 also includes the contact 3 which is open. Hence when car I is taken out of service the relay H! is deenergized, the contact I2 is opened and the contact [0 is closed. With the apparatus in this condition dispatch signals are sent simultaneously to the lower and upper terminals as the contacts I and 9 are closed simultaneously by the camst and 5, and the relays 3 and 13 are simultaneously activated.

If instead of taking car I' out of service, car II is taken out of service by opening its motorgenerator start switch, the coil of the relay I3 is deenergized. This causes the contacts 29 and 2| to be opened. and the contacts 19 and 22 to be closed. With the contact 2! opened and the contacts I? and i9 closed the circuit which includes the contacts II, is, 25, 30 and 34 and the coil of the relay is is open at the contact 34. Since the circuit is open the coil of the relay hi is deenergized and dispatch signals are sent simultaneously to the lower and upper terminals just as they were when car I was taken out of operation.

Taking either car III or car IV out of service instead of car II likewise results in dispatch signals being sent simultaneously to the lower and upper terminals.

If only car V be taken out of service by opening its motor-generator start switch, the relay 3% will be deenergi'zed and the circuit through the coil of the relay l4 will be broken at the contact 35. Current cannot pass through the contact H and the contact 35 as long as the contacts I9, 24 and 29 are open.

It is apparent from the foregoing explanation that taking any one of the five cars of the elevator bank out of service, and thus changing the number of cars left in operation to four, an even number, results in dispatch signals being sent simultaneously to the lower and upper terminals.

If while car I is out of service and consequently the contact H is open and the contact 15 is closed, car II also is taken out 0.5 service, leaving three cars, an odd number, in operation, current can flow through the contacts 15, 22, 25, El and 35 as well as through the coil of the relay it, thus activating the relay and closing the contact I2 and opening the contact it. With the contact #2 closed and the contact iii opened, the relays 8 and it will be energized alternately as the corn tacts 1 and l l are closed alternately by the cams G and 6. Hence with cars III, IV and V in operation, dispatch signals will be sent alternately to the lower and upper terminals. With cars I and III out of operation current will pass through the contacts 16, 28, El, SI and 35 as well as through the coil of the relay M, so that signals will be sent alternately to the lower and upper terminals.

With cars I and IV out of service current will pass through the coil of the relay I4 and through the contacts 16, 2c, 25, 32 and 35. With cars I and V out of service current will pass through the coil of the relay I and through the contacts 5, 29, 25, 30 and 3 With cars II and III out of service current will pass through the coil of the relay M and through the contacts ll, I9, 2?, 3i and 35. With cars II and IV out of service current will pass through the coil of the relay [4 and through the contacts II, If), 25, 32 and 35. With any two cars out of service, leaving three cars, an odd number, in operation the coil of the relay M will be energized and dispatch signals will be sent alternately to the lower and upper terminals.

If three cars are taken out of service leaving two cars, an even number, in operation no current will pass through the coil of the relay M. The contact iii, therefore, will be closed and the contact i2 open and signals will be sent simultaneously to the lower and upper terminals. If, for example, cars I, II and III are taken out of service, the circuit including the contacts i8, 22, 24 and 39 wi l be open at the contact 34 and no current will pass through the coil of the relay M.

The instant invention has been shown as ap plied to a control system for a bank of five elevators, but it is equally applicable to banks of more or less than five elevators. It can be made applicable to a bank of four elevators by omitting one relay such as the relay 23 and its contacts such as contacts 24, 25, 26 and 21 and cross connecting the contacts of the preceding and following groups. It can be made applicable to a group of six elevators by interposing another relay and group of contacts like the relay 23 with its group of contacts 24, 25, 26 and 21.

By incorporating the apparatus of the instant invention into a supervisory control system for a bank of elevators, the maintenance of balanced relationship between the cars serving up traiiic and the cars serving down traffic is taken care of automatically, no matter how many cars are withdrawn from or restored to service.

Having described the invention, I claim:

1. Apparatus forautomatically maintaining a balanced relationship between elevator cars'serving up traffic and elevator cars serving down traflic, said apparatus comprising, in combination, means for sending dispatch signals at regular intervals to one terminal of a bank of elevators, simultaneously acting means for sending a dispatch signal to the other terminal of such bank of elevators each time a dispatch signal is sent to the one terminal, alternately acting means for sending dispatch signals to such other terminal at times intermediate the times when dispatch signals are sent to the one terminal, means for automatically switching said simultaneously acting means into or out of action and at the same time switching said alternately acting means out of or into action so as to implement either said simultaneously acting means or said alternately acting means. but not bothof them at the same time, a circuit for selectively conditioning said means for automatically switching either said simultaneously acting means or said alternately acting means into action, and means controlled by switches employed to withdraw cars of such bank of elevators from service and to restore such cars to service which open and close said circuit as cars are withdrawn or restored, said circuit being so constructed and arranged that whether it is closed or open depends upon whether the number of cars in service is odd or even.

2. Apparatus for automatically maintaining a balanced relationship between elevator cars serving up ,traific and elevator cars serving down traific, said apparatus comprising, in combination, means for sending dispatch signals at regular intervals to one terminal of a bank of elevators, simultaneously acting means for sending a dispatch signal to the other terminal of such bank of elevators each time a dispatch signal is sent to the one terminal, alternately acting means for sending dispatch signals to such other terminal at times intermediate the times when dispatch signals are sent to the one terminal, means for automatically switching said. simultaneously acting means into or out of action and at the same time switching said alternately acting means out of or into action so as to implement either said simultaneously actingmeans or said alternately acting means, but not both of them at the same time, a circuit for selectively conditioning said means for automatically switching either said simultaneously acting means or said alternately acting means into action, and. means controlled by switches employed to withdraw cars of such bank of elevators fromv service and to restore such cars to service which open and close said circuit as cars: are withdrawn or restored, said circuit being soconstructed and arranged that, whether it is closed or open depends upon whether the num- 6 her of cars in service is odd or even, said means for automatically switching said simultaneously acting means into and out of action including a relay which is activated when said circuit is closed and deactivated when said circuit is open.

3. Apparatus for automatically maintaining a balanced relationship between elevator cars serving up trailic and elevator cars serving down traific, said apparatus comprising, in combination, means for sending dispatch signals at regular intervals to one terminal of a bank of elevators, simultaneously acting means for sending a dispatch signal to the other terminal of such bank of elevators each time a dispatch signal is sent to the one terminal, alternately acting means for sending dispatch signals to such other terminal at times intermediate the times when dispatch signals are sent to the one terminal, means for automatically switching said simultaneously acting means into or out of action and at the same time switching said alternately acting means out of or into action so as to implement either said simultaneously acting means or said alternately acting means, but not both of them at the same time, a circuit for selectively conditioning said means for automatically switching either said simultaneously acting means or said alternately acting means into action, and means controlled by switches employed to withdraw cars of such bank of elevators from service and to restore such cars to service which open and close said circuit as cars are withdrawn or restored, said circuit being so constructed and arranged that whether it is closed or open depends upon whether the number of cars in service is odd or even, said means controlled by switches employed to withdraw cars from and restore cars to' service including a plurality of relays and means whereby said relays open and close contacts in said circuit.

4. Apparatus for automatically maintaining a balanced relationship between elevator cars serving up traffic and elevator cars serving down traffic, said apparatus comprising, in combination, means for sending dispatch signals at regular intervals to one terminal of a bank of elevatcrs, simultaneously acting means for sending a dispatch signal to the other terminal of such bank of elevators each time a dispatch signal is sent to the one terminal, alternately acting means for sending dispatch signals to such other terminal at times intermediate the times when dispatch signals are sent to the one terminal, means for automatically switching said simultaneously acting means into or out of action and at the same time switching said alternately acting means out of or into action so as to implement either said simultaneously acting means or said alternately acting means, but not both of them at the same time, a circuit for selectively conditioning said means for automatically switching either said simultaneously acting means or said alternately acting means into action, and means controlled by switches employed to withdraw cars of, such bank of elevators from service and to restore such cars to service which open and close said circuit as cars are withdrawn or restored. said circuit being so constructed and arranged that whether it is closed or open depends upon Whether the number of cars in service is oddv or even, said means controlled by switches employed to withdraw cars from and restore cars to service including a plurality of relays and means whereby said relays open and close contacts in said circuit, each of said relays having a plurality of contacts, each contact of each relay being wired in series with a pair of contacts of another relay, one of said pair of contacts being open and another of said pair of contacts being closed.

Apparatus for automatically maintaining a balanced relationship between elevator cars serving up traffic and elevator cars serving down traffic, said apparatus comprising, in combination, means for sending dispatch signals at regular intervals to one terminal of a bank of elevators, simultaneously acting means for sending a dispatch signal to the other terminal of such bank of elevators each time a dispatch signal is sent to the one terminal, alternately acting means for sending dispatch signals to such other terminal at times intermediate the times when dispatch signals are sent to the one terminal, means for automatically switching said simultaneously actmeans into or out of action and at the same time switching said alternately acting means out of or into action so as to implement either said simultaneously acting means or said alternately acting means, but not both of them at the same time, a circuit for selectively conditioning said means for automatically switching either said simultaneously acting means or said alternately acting means into action, and means controlled by switches employed to withdraw cars of such bank of elevators from service and to restore such cars to service which open and close said circuit as cars are withdrawn or restored, said circuit being so constructed and arranegd that whether it is closed or open depends upon whether the number of cars in service is odd or even, said means controlled by switches employed to withdraw cars from and restore cars to service including a plurality of relays, means whereby said relays open and close contacts in said circuit, said circuit offering alternative paths through the contacts of each relay, part of said paths passing through closed contacts whether said relay be activated or deactivated.

6. Apparatus for automatically maintaining a balanced relationship between elevator cars serving up trafic and elevator cars serving down traflic, said apparatus comprising, in combination, means for sending dispatch signals at reg ular intervals to one terminal of a bank of elevators, simultaneously acting means for sending a dipatch signal to the other terminal of such bank of elevators each time a dispatch signal is sent to the one terminal, alternately acting means for sending dispatch signals to such other terminal at times intermediate the times when dispatch signals are sent to the one terminal, means for automatically switching said simultaneously acting means into or out of action and at the same time switching said alternately acting means out of or into action so as to implement either said simultaneously acting means or said alternately acting means, but not both of them at the same time, a circuit for selectively conditioning said means for automatically switching either said simultaneously acting means or said alternately acting means into action, and means controlled by switches employed to withdraw cars of such bank of elevators from service and to restore such cars t service which open and close said circuit as cars are withdrawn or restored, said circuit being so constructed and arranged that whether it is closed or open depends upon whether the number of cars in service is odd or even, said means controlled by switches employed to with- 8 draw cars from and restore cars to service including a plurality of relays, means whereby Said relays open and close contacts in said circuit, the tworelays adjacent the ends oi the circuit each having two contacts, the intermediate relays each having four contacts.

7. Apparatus for automatically maintaining a balanced relationship between elevator cars serving up traffic and elevator cars serving down trafiic, said apparatus comprising, in combination, means for sending dispatch signals to one terminal of a bank of elevators, simultaneously acting means for sending a dispatch signal to the other terminal of such bank of elevators each time a dispatch signal is sent to the one terminal, alternately acting means for sending dispatch signals to such other terminal at times intermediate the times when dispatch signals are sent to the one terminal, means for automatically switching said simultaneously acting means into or out of action and at the same time switching said alternately acting means out of or into action so as to implement either said simultaneously acting means or said alternately acting means, but not both of them at the same time, a circuit for selectively conditioning said means for automatically switching either said simultaneously acting means or said alternately acting means into action, and means which open and close said circuit as cars are withdrawn from or restored to service, said circuit being so constructed and arranged that whether it is closed or open depends upon whether the number of cars in service is odd or even.

8. Apparatus for automatically maintaining a balanced relationship between elevator cars serving up traflic and elevator cars serving down traffic, said apparatus comprising, in combination, means for sending dispatch signals to one terminal of a bank of elevators, simultaneously acting means for sending a dispatch signal to the other terminal of such bank of elevators each time a dispatch signal is sent to the one terminal, alternately acting means for sending dispatch signals to such other terminal at times intermediate the times when dispatch signals are sent to the one terminal, means for automatically switching said simultaneously acting means into or out of action and at the same time switching said alternately acting means out of or into action so as to implement either said simulaneously acting means or said alternately acting means, but not both of them at the same time, a circuit for selectively conditioning said means for automatically switching either said simultaneously acting means or said alternately acting means into action, and means which open and close said circuit as cars are withdrawn from or restored to service, said circuit being so constructed and arranged that whether it is closed or open depends upon whether the number of cars in service is odd or even, said means for automatically switching said simultaneously acting means into and out of action including a relay which is activated when said circuit is closed and deactivated when said circuit is open 9. Apparatus for automatically maintaining a balanced relationship between elevator cars servmg up trafiic and elevator cars serving down traflic, said apparatus comprising, in combinatlon, means for sending dispatch signals to one terminal of a bank of elevators, simultaneously acting means for sending a dispatch signal to the other terminal of such bank of elevators each time a dispatch signal is sent to the one terminal,

9 alternately acting means for sending dispatch signals to such other terminal at times intermediate the times when dispatch signals are sent to the one terminal, means for automatically switching said simultaneously acting means into or out of action and at the same time switching said alternately acting means out of or into action so as to implement either said simultaneously acting means or said alternately acting means, but not both of them at the same time, a circuit for selectively conditioning said means for automatically switching either said simultaneously acting means or said alternately acting means into action, and means which open and close said circuit as cars are withdrawn from or restored to service, said circuit being so constructed and arranged that whether it is closed or open depends upon whether the number of cars in service is odd or even, said means controlled by switches employed to withdraw cars from and restore cars to service including a plurality of relays and means whereby said relays open and close contacts in said circuit.

10. Apparatus for automatically maintaining a balanced relationship between elevator cars serving up traflic and elevator cars serving down traffic, said apparatus comprising, in combination, means for sending dispatch signals to one terminal of a bank of elevators, simultaneously acting means for sending a dispatch signal to the other terminal of such bank of elevators each time a dispatch signal is sent to the one terminal, alternately acting means for sending dispatch signals to such other terminal at times intermediate the times when dispatch signals are sent to the one terminal, means for automatically switching said simultaneously acting means into or out of action and at the same time switching said alternately acting means out of or into action so as to implement either said simultaneously acting means or said alternately acting means, but not both of them at the same time, a circuit for selectively conditioning said means for automatically switching either said simultaneously acting means or said alternately acting means into action, and means which open and close said circuit as cars are withdrawn from or restored to service, said circuit being so constructed and arranged that whether it is closed or open depends upon whether the number of cars in serv- 50 ice is odd or even, said means controlled by switches employed to withdraw cars from and restore cars to service including a plurality of relays and means whereby said relays open and 10 close contacts in said circuit, each of said relays having a plurality of contacts, each contact of each relay being wired in series with a pair of contacts of another relay, one of said pair of contacts being open and another of said pair of contacts being closed.

11. Apparatus for automatically maintaining a balanced relationship between elevator cars serving up trafiic and elevator cars serving down traffic, said apparatus comprising, in combination, means for sending dispatch signals to one terminal of a bank of elevators, simultaneously acting means for sending a dispatch signal to the other terminal of such bank of elevators each time a dispatch signal is sent to the one terminal, alternately acting means for sending dispatch signals to such other terminal at times intermediate the times when dispatch signals are sent to the one terminal, means for automatically switching said simultaneously acting means into or out of action and at the same time switching said alternately acting means out of or into ac tion so as to implement either said simultaneously acting means or said alternately acting means, but not both of them at the same time, a circuit for selectively conditioning said means for automatically switching either said simultaneously acting means or said alternately acting means into action, and means which open and close said circuit as cars are withdrawn from or restored to service, said circuit being so constructed and arranged that whether it is closed or open depends upon whether the number of cars in service is odd or even, said means controlled by switches employed to withdraw cars from and restore cars to service including a plurality of relays for means whereby said relays open and close contacts in said circuit, said circuit offering alternative paths through the contacts of each relay, part of said paths passing through closed contacts whether said relay be activated or deactivated.

WALTER A. NIKAZY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,608,094 Finnegan Nov. 23, 1926 2,224,808 Carson Dec. 10, 1940 2,262,393 Eames Nov. 11, 1941 2,266,779 Loughridge Dec. 23, 1941 

